Kensington Publishing Corp. is an American book publisher specializing in mass market paperback, trade paperback and hardcover books, founded in 1974 by Walter Zacharius and Roberta Bender Grossman. Kensington acquired Pinnacle Books in 1988 and Citadel Press in 2000. Citadel is the focal point for Kensington's non-fiction program, which includes the popular Citadel's "100" series. In 2008, Kensington acquired the publishing assets of Holloway House (publishers of Iceberg Slim).